Reclosable flip top cartons are not new in the art. For example, U.S. Pat. No. 3,942,712 issued to P. L. Bundy on Mar. 9, 1976 discloses a carton having lock tabs on the cover portion adapted to engage V-shaped slits in the receptacle portion for reclosing and having lines of weakness initially connecting the cover and receptacle portions. U.S. Pat. No. 4,048,052 issued to W. M. Tolaas on Sept. 13, 1977 comprises a reclosable cover portion hingedly connected to a receptacle portion by a score line at the top edge of the rear receptacle panel. The carton is opened by severing lines of weakness on both sides and the carton is reclosed by mating the leading edge of a locking flange hingedly connected to the top edge of the front receptacle panel with a slit on the inner section of the front cover panel. U.S. Pat. No. 4,083,455 issued to M. Keating, Jr. on Apr. 11, 1978 discloses a carton having inside front panel flaps on the cover portion adapted to mate with downwardly extending front panel flaps on the receptacle portion for locking and having lines of weakness diagonally positioned along both side walls to initially connect the cover portion to the receptacle portion.
In addition, the use of an arcuate edge on the front panel of a cover portion adapted for reclosing a carton is known. U.S. Pat. No. 3,078,030, issued to R. T. Gorton on Feb. 19, 1963 discloses a carton comprising a tongue panel that is sandwiched between an outer front cover panel and an inner front cover panel and that is adapted to mate with a cutout section of the front panel of the receptacle portion. The carton is initially opened by severing lines of weakness along both carton sides connecting the cover portion with the receptacle portion. U.S. Pat. No. 3,861,583 issued to W. E. Tingley and J. Addiego on Jan. 21, 1975 discloses a reclosable carton having a closure panel on the cover portion with an arcuate edge that inserts into a slit in the front panel of the receptacle portion. Lines of weakness are provided along the front panel of the receptacle portion to initially connect the closure panel to the front receptacle panel. U.S. Pat. No. 2,361,597 issued to K. T. Buttery on Oct. 31, 1944 discloses a box or container having a rectangular-shaped tongue extending from the front panel of the cover portion that is adapted to fit into a slit on the front panel of the receptacle portion. Lines of weakness are positioned horizontally along both side walls for initial connection of the cover portion to the receptacle portion.
Finally, it is known to employ an arcuate shaped edge on the front panel of a cover portion of the carton to simply tuck behind the front panel of the receptacle portion for reclosing. U.S. Pat. No. 395,886 issued to W. H. Emery on Jan. 8, 1889 discloses a carton having a front closing flap that ends in a generally arcuate shape and which is designed to tuck behind an outer front flap and in front of an inner front flap for carton closure.
The prior art discloses a number of means for providing initial closure of the carton and for reclosure after opening. Frequently, the prior art cartons employ relatively complex mating panel sections for reclosure or require the insertion of a tongue element into a mating slot. The carton elements involved in these types of reclosures are easily damaged after repeated use. In addition, the more complex reclosure designs require substantially more board than relatively simple reclosures. Even when the reclosure means is relatively simple, the carton is usually designed to require a rather precise manipulation of a reclosure tongue or panel element into a slot or between an inner and an outer wall.
Additionally, the design for the lines of weakness that initially close the carton has been primarily directed at ensuring that the carton will not open during shipment. As a consequence, the lines of weakness are often overdesigned and tend to require considerable effort to sever. None of the prior art cartons make use of a simple reclosure design comprising an arcuate edge on the reclosure panel that simply tucks behind the front wall, in combination with lines of weakness on both sides of the carton designed to be the minimum necessary to prevent the carton from opening during shipment. The combination results in a package that makes very efficient use of board and is easily opening and easily reclosed. The consumer does not need to pull tear strips, fight the adhesive seal, struggle with severing the lines of weakness nor struggle with trying to reclose the carton.
Therefore, it is an object of the present invention to provide a carton that requires only simple, gross manipulation to effect reclosure.
It is a further object of the present invention to provide a carton that can be opened with a minimum of force and yet is capable of withstanding the rigors of shipping.
Finally, it is an object of the present invention to provide a carton that uses a minimum of board and can be erected on standard carton assembly equipment and is therefore economical to manufacture.